FreeNAS - possible to add a disk for RAID1?

[msloane]

Hi....

I have a working FreeNAS server with one 300GB ATA HDD. I've got my MP3 and digital photo collection on the drive, and everything works great.

This may be a naive question, but is there a reasonably straightforward method* for adding another (identical) HDD to the system and, after reconfiguring and mirroring the data, have it come up in a RAID1 configuration?

*(Meaning, without reformatting, moving, and/or losing data on the existing HDD.)

Thanks....